code manipulation : class proxy(cglib, bytebuddy)

code-manipulation/dynamic-proxy/pom.xml

@@ -25,6 +25,19 @@
       <version>4.11</version>
       <scope>test</scope>
     </dependency>
+
+    <dependency>
+      <groupId>cglib</groupId>
+      <artifactId>cglib</artifactId>
+      <version>3.3.0</version>
+    </dependency>
+
+    <dependency>
+    <groupId>net.bytebuddy</groupId>
+    <artifactId>byte-buddy</artifactId>
+    <version>1.10.20</version>
+  </dependency>
+
   </dependencies>
 
 </project>

code-manipulation/dynamic-proxy/src/main/java/org/example/class_proxy/Book.java

@@ -0,0 +1,24 @@
+package org.example.class_proxy;
+
+public class Book {
+
+    private Integer id;
+
+    private String title;
+
+    public Integer getId() {
+        return id;
+    }
+
+    public void setId(Integer id) {
+        this.id = id;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public void setTitle(String title) {
+        this.title = title;
+    }
+}

code-manipulation/dynamic-proxy/src/main/java/org/example/class_proxy/BookService.java

@@ -0,0 +1,10 @@
+package org.example.class_proxy;
+
+public class BookService {
+    public void rent(Book book) {
+        System.out.println("rent: " + book.getTitle());
+    }
+    public void returnBook(Book book) {
+        System.out.println("return: " + book.getTitle());
+    }
+}

code-manipulation/dynamic-proxy/src/test/java/org/example/class_proxy/BookServiceTest_ByteBuddy.java

@@ -0,0 +1,39 @@
+package org.example.class_proxy;
+
+import net.bytebuddy.ByteBuddy;
+import net.bytebuddy.implementation.InvocationHandlerAdapter;
+import net.bytebuddy.matcher.ElementMatchers;
+import net.sf.cglib.proxy.Enhancer;
+import net.sf.cglib.proxy.MethodInterceptor;
+import net.sf.cglib.proxy.MethodProxy;
+import org.junit.Test;
+
+import java.lang.reflect.InvocationHandler;
+import java.lang.reflect.Method;
+
+public class BookServiceTest_ByteBuddy {
+
+    @Test
+    public void proxy_byteBuddy() throws Exception {
+        Class<? extends BookService> proxyClass = new ByteBuddy().subclass(BookService.class)
+                .method(ElementMatchers.named("rent")).intercept(InvocationHandlerAdapter.of(new InvocationHandler() {
+                    BookService bookService = new BookService();
+                    @Override
+                    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
+                        System.out.println("로깅!!");
+                        Object invoke = method.invoke(bookService, args);
+                        System.out.println("다른 작업!!");
+                        return invoke;
+                    }
+                }))
+                .make().load(BookService.class.getClassLoader()).getLoaded();
+        BookService bookService = proxyClass.getConstructor(null).newInstance();
+
+        Book book = new Book();
+        book.setTitle("spring");
+
+        bookService.rent(book);
+        bookService.returnBook(book);
+
+    }
+}

code-manipulation/dynamic-proxy/src/test/java/org/example/class_proxy/BookServiceTest_CGlib.java

@@ -0,0 +1,36 @@
+package org.example.class_proxy;
+
+import net.sf.cglib.proxy.Enhancer;
+import net.sf.cglib.proxy.MethodInterceptor;
+import net.sf.cglib.proxy.MethodProxy;
+import org.junit.Test;
+
+import java.lang.reflect.Method;
+
+public class BookServiceTest_CGlib {
+
+    @Test
+    public void proxy_cglib() {
+        MethodInterceptor handler = new MethodInterceptor() {
+            BookService bookService = new BookService();
+            @Override
+            public Object intercept(Object o, Method method, Object[] args, MethodProxy methodProxy) throws Throwable {
+                if (method.getName().equals("rent")){
+                    System.out.println("로깅!!");
+                    Object invoke = method.invoke(bookService, args);
+                    System.out.println("다른 작업!!");
+                    return invoke;
+                }
+                return method.invoke(bookService, args);
+            }
+        };
+        BookService bookService = (BookService) Enhancer.create(BookService.class, handler);
+
+        Book book = new Book();
+        book.setTitle("spring");
+
+        bookService.rent(book);
+        bookService.returnBook(book);
+
+    }
+}